Pyrotechnic composition



FXPTQQQ HARRY J. NICHOLS, OF WASHINGTON, DISTRICT OF COLUMBIA.

PYROTECHNIC COMPOSITION.

No Drawing.

To all whom it may concern:

Be it known that I, HARRY J. NIoHoLs, a citizen of the United States, residing at \Vashington, District of Columbia, have invented new and useful Improvements in Pyrotechnic Compositions, of which the following is a specification.

This invention relates to improvements in pyrotechnic composition and has for its object the production of a pyrotechnic mixture adapted to produce a brilliant flame of great luminosity and at the same time a large volume of dense smoke of great persistency and obscuring power.

Another object is to provide a pyrotechnic mixture of the above general nature particularly adapted for use in signalling apparatus at any time of the day or night.

A further object is to provide a pyrotechnic mixture adapted to burn with great persistency and one which will not be extinguished either by high velocity winds or submersion in water.

A further object is to provide a pyrotechnic mixture which will be safe to handle and manipulate which will not deteriorate 01' age during long storage periods and will burn with long duration and produce the maximum amount of flame and smoke per unit of volume.

The preferred embodiment of pyrotechnic mixture hereinafter described includes a mixture of preferably red or amorphous phosphorus, powdered manganese dioxide, powdered metallic magnesium, zinc oxide and boiled linseed oil.

In preparing one form of the composition I prefer to use the following ingredients in substantially the following proportions Red phosphorus 50 parts.

Boiled linseed oil 2 parts. Zinc oxide 3 parts. Powdered magnesium 10 parts. Wanganese dioxide 34 parts.

Red phosphorus l755% Boiled linseed oil 2- 4% Zinc oxide 2 6% Powdered magnesium 7-12% Powdered manganese dioxide 30-38% Specification of Letters Patent.

Patented June 13, 1922.

Application filed March 30, 1921. Serial No. 456,986.

It has been found that part of the magnesium metal used in the pyrotechnic mixture may be replaced by powdered aluminum metal, without any considerable detriment to the quality of the signal produced, or an alloy of magnesium and aluminum reduced to powdered form may be used. In this case, I prefer to use the ingredients in about the following proportions Phosphorus 50 parts. Boiled linseed oil 2 parts. Zinc oxide 3 parts. Manganese dioxide 35 parts. Powdered aliuninum 5 parts. Powdered magnesium: 5 parts.

In preparing this compound the ingredients should preferably be mixed as follows:The red phosphorus and boiled linseed oil first being mixed thoroughly, the zinc oxide is next added and mixed, and the powdered magnesium metal then added and mixed. The manganese dioxide should be added to the composition last as the composition is more sensitive and inflammable after the manganese dioxide is added. The red phosphorus used in the composition should be a good grade of red phosphorus free from impurities, particularly white or yellow phosphorus, or phosphoric acid since these impurities may cause the mixture to ignite spontaneously during mixing.

The amounts of magnesium and manganese dioxide to be employed depend on the duration of burning desired since an increase in these materials makes the composition more active and quicker in burning. The zinc oxide and the phosphorus produce an opposite effect so that by varying the percentages of magnesium and zinc oxide, or manganese dioxide and phosphorus, the rate of burning can be controlled through wide limits. The zinc oxide further assists in the production of a dense white, presistent smoke. The manganese dioxide should be of a purity of at least 85% and should be very finely divided. Other desensitizing materials such as parafiine, shellac or stearic acid may be used in place of the boiled linseed oil, though the last named ingredient is to be preferred particularly where the pyrotechnic composition is to be moulded under pressure.

My composition produces a large brilliant white flame oi great luminosity and a large volume of dense white smoke of great persistency and obscuring power; does not clog openings or orifices of containers in which it is burnt; is not extinguished by violent winds or submersion in Water; has a high chemical etliciency; and when burned in a long tube or through an orifice, the volatile products of combustion burn only after emerging from the opening or orifice thus producing a signal of uniform intensity throughout the duration of burning. It possesses in a high degree all the desired properties of mpyrotechnic mixture for use in the special pyrotechnic devices herein mentioned. as well as for use generally Where a pyrotechnic signal is to be produced under adverse conditions.

From the above it will be seen that the present invention provides a simple and practical compound adapted to accomplish among others all of the objects herein described.

\Yhat I claim is:

1. A pyrotechnic composition for use in signalling devices including red pllOSpllOlUS. metallic oxides, light metals in powdered form and a desensitizing material.

A pyrotechnic composition for use in signalling devices including red phosphorus, metallic oxides, aluminum and magnesium, all in powdered form, and a desensitizing material.

3. A pyrotechnic composition for use in signalling devices including red phosphorus, manganese dioxide, zinc oxide, magnesium metal. and aluminum, all in powdered form, and linseed oil as a desensitizing material.

l. .i pyrotechnic composition adapted to produce a brilliant flame and large (plantities of smoke for use in signalling devices including substantially 50 parts of red phosphorus. '15 parts of manganese dioxide, parts of zinc oxide, parts o't magnesium, 5 parts o'l aluminum and 52 parts oi boiled linseed oil.

Signed at \Vashington, District of Columbia, this 11th day of February, 1921.

HARRY J. NICHOLS. 

